Add a docker app version to the bundle custom section

Signed-off-by: Silvin Lubecki <silvin.lubecki@docker.com>

Author: silvin-lubecki

internal/packager/cnab.go

@@ -172,7 +172,7 @@ func ToCNAB(app *types.App, invocationImageName string) (*bundle.Bundle, error)
 		SchemaVersion: CNABVersion1_0_0,
 		Custom: map[string]interface{}{
 			internal.CustomDockerAppName: DockerAppCustom{
-				Version: DockerAppCustomVersionCurrent,
+				Version: DockerAppPayloadVersionCurrent,
 				Payload: payload,
 			},
 		},

internal/packager/cnab_test.go

@@ -6,6 +6,8 @@ import (
 	"regexp"
 	"testing"
 
+	"github.com/docker/app/internal"
+
 	"github.com/docker/app/types"
 	"gotest.tools/assert"
 	"gotest.tools/golden"
@@ -20,7 +22,7 @@ func TestToCNAB(t *testing.T) {
 	assert.NilError(t, err)
 	s := golden.Get(t, "bundle-json.golden")
 	expectedLiteral := regexp.QuoteMeta(string(s))
-	expected := fmt.Sprintf(expectedLiteral, DockerAppCustomVersionCurrent, `\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}.\d+Z`)
+	expected := fmt.Sprintf(expectedLiteral, DockerAppPayloadVersionCurrent, `\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}.\d+Z`, internal.Version)
 	matches, err := regexp.Match(expected, actualJSON)
 	assert.NilError(t, err)
 	assert.Assert(t, matches)

internal/packager/custom.go

@@ -10,16 +10,19 @@ import (
 
 const (
 	// DockerAppCustomVersion1_0_0 is the custom payload version 1.0.0
-	DockerAppCustomVersion1_0_0 = "1.0.0"
+	DockerAppPayloadVersion1_0_0 = "1.0.0"
 
 	// DockerAppCustomVersionCurrent the current payload version
-	DockerAppCustomVersionCurrent = DockerAppCustomVersion1_0_0
+	// The version must be bumped each time the Payload format change.
+	DockerAppPayloadVersionCurrent = DockerAppPayloadVersion1_0_0
 )
 
 // DockerAppCustom contains extension custom data that docker app injects
 // in the bundle.
 type DockerAppCustom struct {
-	Version string          `json:"version,omitempty"`
+	// Payload format version
+	Version string `json:"version,omitempty"`
+	// Custom payload format depends on version
 	Payload json.RawMessage `json:"payload,omitempty"`
 }
 
@@ -28,16 +31,26 @@ type CustomPayloadCreated interface {
 	CreatedTime() time.Time
 }
 
+// CustomPayloadAppVersion is a custom payload with a docker app version
+type CustomPayloadAppVersion interface {
+	AppVersion() string
+}
+
 type payloadV1_0 struct {
 	Created time.Time `json:"created"`
+	Version string    `json:"app-version"`
 }
 
 func (p payloadV1_0) CreatedTime() time.Time {
 	return p.Created
 }
 
+func (p payloadV1_0) AppVersion() string {
+	return p.Version
+}
+
 func newCustomPayload() (json.RawMessage, error) {
-	p := payloadV1_0{Created: time.Now().UTC()}
+	p := payloadV1_0{Created: time.Now().UTC(), Version: internal.Version}
 	j, err := json.Marshal(&p)
 	if err != nil {
 		return nil, err
@@ -53,7 +66,7 @@ func CustomPayload(b *bundle.Bundle) (interface{}, error) {
 	}
 
 	switch version := custom.Version; version {
-	case DockerAppCustomVersion1_0_0:
+	case DockerAppPayloadVersion1_0_0:
 		var payload payloadV1_0
 		if err := json.Unmarshal(custom.Payload, &payload); err != nil {
 			return nil, err

internal/packager/custom_test.go

@@ -42,7 +42,7 @@ func TestCustomPayloadNil(t *testing.T) {
 		},
 		{
 			testName: "NoPayload",
-			version:  DockerAppCustomVersionCurrent,
+			version:  DockerAppPayloadVersionCurrent,
 			payload:  nil,
 		},
 	}
@@ -58,12 +58,13 @@ func TestCustomPayloadNil(t *testing.T) {
 
 func TestCustomPayloadV1_0_0(t *testing.T) {
 	now := time.Now().UTC()
-	b := createBundle(t, DockerAppCustomVersion1_0_0, payloadV1_0{now})
+	b := createBundle(t, DockerAppPayloadVersion1_0_0, payloadV1_0{now, "version"})
 	payload, err := CustomPayload(&b)
 	assert.NilError(t, err)
 	v1, ok := payload.(payloadV1_0)
 	assert.Assert(t, ok)
 	assert.Assert(t, now.Equal(v1.CreatedTime()))
+	assert.Equal(t, "version", v1.AppVersion())
 }
 
 func createBundle(t *testing.T, version string, payload interface{}) bundle.Bundle {

internal/packager/testdata/bundle-json.golden

@@ -184,7 +184,8 @@
     "com.docker.app": {
       "version": "%s",
       "payload": {
-        "created": "%s"
+        "created": "%s",
+        "app-version": "%s"
       }
     }
   }